1. Field of the Invention
The present invention relates to a measurement unit, a transportation system, and a measurement method. In particular, the present invention relates to a technique of enabling data measured by the measurement unit to be analyzed even if an environment of the measurement unit, i.e., a state in which the measurement unit is placed, is not clear at the time of measurement.
2. Description of the Related Art
It has been proposed to transport a measurement unit equipped with sensors such as a particle sensor and a vibration sensor by a transportation apparatus such as a stacker crane to obtain environmental data during transportation and during storage in a rack or the like (See, for example, JP4168123B). According to JP4168123B, the measurement unit outputs measurement data to a transportation apparatus such as a stacker crane. In the transportation apparatus, data such as a state of the measurement unit is added to the measurement data, and the resulting data is outputted to a system controller. However, if the transportation apparatus does not have any communication device with the measurement unit, since the measurement unit cannot obtain data indicating the state, e.g., data indicating whether the measurement unit is being transported or the measurement data is stored, these items of data cannot be added to the measurement data. Therefore, the measurement data cannot be analyzed on the ground. Thus, in the transportation apparatus that does not have any device for communicating with the measurement unit, measurement of the environment using the measuring unit cannot be performed.